Technical Field
The present disclosure relates to a resonator and a resonator array. More particularly, the present disclosure relates to a microelectromechanical system (MEMS) resonator and a resonator array.
Description of Related Art
A resonator, an electric element which resonates at a resonant frequency, is widely used in electronic products. Owing to the miniaturization and high quality demands of the electronic products, there is a need to develop a resonator with high quality factor (Q).
Piezoelectric MEMS resonators are resonators with high performance which are manufactured by using the MEMS technique. The piezoelectric resonators can be configured for signal filtering by translating electric signals to mechanical vibrations via piezoelectric layers and outputting electric signals again. Such piezoelectric MEMS resonators have high reliabilities and can be used in packages with different sizes, as a result, the piezoelectric MEMS resonators are popular.
A conventional MEMS resonator includes a resonator body and two arms disposed at two sides of the resonator body. One end of the arm is secured on the substrate to allow the resonator body being suspended, and electrodes and piezoelectric layers are disposed at both the resonator body and the arms. The MEMS resonators with such structure have lots of energy loss, such as an anchor loss and a thermoelastic damping; as a result, the quality factor cannot be increased.
Therefore, how to improve the structure of MEMS resonators to increase the quality factor becomes a pursuit target for practitioners.